First of all, don't try to sell me on XF: it is already my #1 pick. But our dilemma is that we are on a server where we are near the end of the rope--we run vB 3.7 and it is a "big board" with 7.5 million posts, hundreds of thousands of threads, etc. Online, about 700-800 users during peak hours. From what I've read here, XF is of course better on resources. But, by how much, and which version? I do know that it would be suicide on our server by upgrading (UPgrading?) to vB 4.x. Someone at another forum (which shall remain nameless) said that in vB 4.2, the resource issues have been addressed and it works much better. I find that highly difficult to believe, since the forum would need a total rewrite to be more efficient. A few tweaks? Yes. But I still can't get over the idea that 4.x series put a bigger hit on resources overall than the 3.7/3.8 series...and as of yet, we are still on 3.7 since I did not want to take the hit. We're trying to sell this to the forum owner and staff. Some of the staff have used it and like it, so that is not really an issue. But we currently own the 4.x full license and we're trying to justify it monetarily. I don't intend XF to be the cure for our nearly overtaxed server, but I do feel that I should not have to throw more expensive hardware at what amounts to sloppy coding in vB4. And if XF will help us best utilize the service we have through more efficient coding, then that is all for the better. I'm most curious to see if anyone has insight as to performance of vB 3.7 or 3.8 compared to vB 4.2, put up against XF. I realize this won't get much input, but I've already skimmed the few threads here I've searched for over the past few months, and haven't really seen exactly what I'm looking for. I also figured with a few *ahem* former vB folks hanging in these hallowed halls, I may get better input than I'd have gotten in the past. Thanks much!