This is a really good plugin to use for smelting.  It's the only one that I've found that doesn't break my everlight plugin. The dev is very responsive and helpful if problems arise. Had some trouble when it was switched over to harmony but it all seems to be ironed out now. No a bit of lag that I've noticed and it's very easy to set up. I would highly recommend.

Im using more then a month now, the modder updates, reply etc, Pluging never got me problems, its a nice pluging, doing that review to see if stars goes up, it deserve more!

nice plugin, very cheap quick support 

Edit: Well, it worked well for a matter of 24 hours. After 24 hours, I started having massive amounts of GARBAGECOLLECT issues, excessive hook call times, and it lags my servers down to a stall. Every time a player turns on a furnace it does this. Even if it's just one. Tried to troubleshoot with the developer, but have not heard back and unfortunately I will have to find another plugin.  I'll give it 2 because of the simplicity in the configuration, but it's completely unusable until this is fixed.

This plugin is amazing! First day in of using it and I have a lot of very happy players! It gives us so much room to work with when it comes to smelting rates, multipliers, and outputs. Super easy to configure and it seems like it's so much better on performance than the heavy UI alternatives! If you're considering this plugin.....just do it! You won't be disappointed.

I genuinely had high hopes for this plugin when I purchased it. This was one of the first plugins that was updated to work with the electric furnaces that I was able to find available for purchase. However, upon installing this plugin live on my main server, I quickly became aware of multiple issues within the plugin that made it unusable on my server. I have opened tickets for two of the items, but gave up attempting further inquiries as after my initial conversation with the developer, they have been quite slow to respond. So why am I giving this a 2-star review.

The first main issue I noticed is the config file is incredibly sensitive and quite limited when attempting to manipulate the fuel consumption of this plug. The current format of this plugin would indicate that if you attempt to lower the fuel consumption below 10, it will completely reset all changes to the config file. This problem became quite annoying when attempting to set up more than one line on the config file, as you will lose all data which was changed. So you might be asking yourself why lowering the fuel consumption would be important... This was a change I was attempting to make as the fuel consumed when using Furnace Splitter and Quick Smelt, the fuel consumed would be about half of what was indicated as being needed. However, with this plugin and Furnace Splitter the fuel listed as being needed would run out before the ore was processed, and it was showing about half of what was required to process the ore. This quickly became quite annoying to the players on my server.

The second main issue I noticed within this plugin is the charcoal produced for players on the server would vary significantly. When setting the config file to give 1 charcoal for every 10 fuel consumed with a 75% chance at charcoal, about half of the players on the server would see a 1.1 to 1.3 fuel:charcoal ratio. However, the rest of the players were split between having either the large or normal furnace produce the rates mentioned previously, but the other sources would be a 10:1 fuel to charcoal ratio, or they had the 10:1 fuel to charcoal ratio as the config file would indicate should happen. So once again, why is this a problem? Well for roughly half of the server if I have the config file set to a 10:8 fuel to charcoal ration at a 75% chance which would be what should be expected in general, they would be receiving an INSANE amount of charcoal. I was personally seeing a 1 to 20 fuel to charcoal ratio, with the 10:8 setting at 75%. As I allow players to sell unused resources for server points, that bug would have broken the economy of my server by leaving it in place at the required rate so that all players should receive 8 charcoal for 10 wood consumed.

I gave this plugin a 2-star review as 2.5 was not available. The fact that the electric furnaces worked and could be sped up means to me that it is worth at minimum 2.5 stars. But as there are far too many bugs with this plugin that have yet to be resolved, I have had to remove this plugin entirely from my server. I would suggest checking if this plugin will be impacted by others before installing it on your server. Also, you will need patience if you send in a support ticket.

Edit for Author response: If the charcoal output is adjusted so that everyone on the server is getting results similar to the CFG setup, I will increase the rating 1 star. If the fuel consumption can be tweaked by the server admin, I will increase the rating 1 additional star. Ultimately, I am not sure as though I will be able to give this plugin a 5-star review for a few reasons. The main issue I have with the limited function of the CFG file is... Why have items which can be changed that result in the entire CFG file being rewritten as a default CFG? I had to enter the information into the CFG a few times before I realized which field was causing the entire CFG to be rewritten. That is the "limits" of the CFG, not functions which can be changed. I was quite specific in the "Quote" you wrote there as to what I meant. I am not sure what the fuel consumption rates would have had with limiting the plugin/cfg would have caused a server to stall, as it is a value that will be called regardless to consume fuel... As I wrote in the edited response, I will increase my rating of this plugin if it becomes functional from my perspective as a server admin. Fortunately for me at the moment, there is a version of Quick Smelt that works with Electric Furnaces, so I have just switched back to the original plugin my server was using.

Charcoal produced appears to be close to default for most / all players potentially so I increased the rating 1 star as I stated I would.

It is simple to tune cook times per item type and modify resource ratios making it an accessible choice for all kinds of server owners.
So far seems like a good solution for controlling my server furnace's smelting without a noticeable impact on performance.