obsidian,
Mapping for Q3 in the early days was just as bad as Q4 is today. Q3 ran relatively slow on hardware back then, most people on dialup couldn't play reliably online, lots of bugs crippling the game, q3radiant had it's own little querks. I didn't play Q3 the first year it was released and I didn't start mapping for another year, instead working with Half-Life.
Hmm... I wanted to say for me it ran on ISDN all along (Q3A that is), but then remembered I played Q3A at University with a 10 MBit connect. So I have no idea how Q3A ran on ISDN in the beginning. But later on it ran great, or as good as a game can run on ISDN. Whereas with Q4 I have the feeling it will never run that well. Dual ISDN, as Todtsteltzer points out, to me sounds like "forget ISDN". But as long as I have not tested it online, I am withholding any judgement.
A point I'd like to make anyway is this: Back for Q3A I was playing every test version and demo, and got Q3A as soon as it was released. Presently I still have not bought Q4. So some of the "must have right this moment glam" seems to have gone. I still think that Q4 SP will be nice, and definitely be worth playing, just presently I can wait (BTW: Fear is another case were I will wait for the Bargain bin). In both cases I am hoping for patches that optimize FPS.
Another personal point: Usually I would get excited about new tech, if it would actually let me make something that was previously not possible. Well for Far Cry it was (easy editing) terrain and massive vegetation, with nice SP AI for stunning never before seen outdoor landscapes. And most of the editing is happening in real time.
With D3 that was also a step into the real time domain of editing. But the light source counts are such a limitation IMO, that all the fun is taken out of mapping. Especially because I do *not* want to do horror/dark maps.
I could imagine giving Prey a try though, should they have come up with some nice gaming additions.
As that may be, I respect those folks that actually do something. And once I have Q4, I am sure I will download the MP maps, just to see what can be done.