0. I just advised a 4* knight NOT to upgrade his khorovod to a sudaruska.
1. Sudaruska/Khorovod both require their charge attacks to be worthwhile. All bombs, the brandishes, catalyzers, leviathan blade, thorn blades etc. also require their charge attacks to compete with weapons that don't need CTR. Wait no, the brandishes just kill everything regardless of their heat. My bad.
2. The knight in question would be unable to run shadow lairs for money. Khorovod/Sudaruska+plate mail won't get him anywhere. This means that to upgrade his Sudaruska to 5*, the knight would have to pay the supply depot. In fact, quite a few knights are shockingly unable to run UFSC on elite mode daily to receive their fire crystals to make their first set of 5* gear. Buying the fire shards with the crowns that they've earned would take them quite a while, might not pan out well (if the another source of radiants is found), and prevents them from making gear that would help them more than heating their one 5* weapon.
3. Taking this on the whole, all 4* weapons with "usable" charge attacks are now better than their 5* counterparts.
4. Actually, as Zeddy points out, if you cannot get a weapon fully heated or at least heated to around level 7 or 8, it will simply be a downgrade from the superior 4* version in terms of damage. The only (real, real meaning that you want to improve your gear) reason to upgrade at that point would be some sort of a difference in functionality, e.g. another bounce on your alchemer.
I would like to see revisions made to the guides on the wiki, as well as Bopp's sword guide based on the fact that 4* knights upgrading to 5* will be unable to heat their weapons in a timely manner. We set the standards for pretty much anyone that speaks English and plays Spiral Knights, and I would say that this is a noteworthy change in the game.
Specifically, there needs to be an easily removable (as this balance could change) section that comes before the 5* descriptions of weapons etc. explaining to newer players why they can't have the "good gear" until they're able to beat UFSC, are using 5* weapon trinkets, or find enough time to farm 5* fire crystals. Chaos set would also remedy this, though most knights would have a hard time playing with chaos as their first set once they reached 5*, and would likely be better off not using charge attacks.
The other point to this is that when people come on here asking stuff about "which 5* gear is better", this should be first on your mind when you respond. "What should my 5* gear be?" should be answered with "Your 5* gear should be kept at 4* until you are prepared to heat it."
The "new" way to use weapons should go something like:
0. Craft weapons to 4*.
1. Build 5*/armors to support your 4* weapons.
2. Eventually find the resources to heat the weapons, focusing solely on the weapon you want to heat. Crafting other weapons is great, but since you can't heat them to 10, it just wastes crowns that could be spent on going to UFSC/buying from the supply depot. This should be done after they've made most of their arsenal, and have little else to do.
3. Once enough resources are farmed to heat the weapon up a good bit, craft the 5* and proceed as usual.
Thanks, Fehzor.
I don't think that I used any foul or even remotely questionable language in this post, but if I did I would like to first apologize and second ask for someone to tell me so that I can change it before my ability to post is removed.
Welcome back, Fehzor! We've missed you. The people around are driving me nuts!
I'd like you to take this into consideration. Do note that I will indeed have to post that link so many times I'm going to, as you once suggested Bopp should, link to where I last used the link rather than link to the actual post I intend to show.