Just curious as to what types of indoor mat/floor people train on. It would be ideal for a dojo to have both mat and hardwood, but square area in smaller dojos usually don't allow for any practical combo (unless you go with a folding mat), so it needs to be one or the other. In the past 10 years or so, mat flooring has really come a long way. Remember the interlocking square puzzle mats? then, there was the pad with cover like a huge pool lining, slippery as hell with sweat on it.
The common seamless cross-linked polyethylene foam with vinyl/polyester covering is half decent. but what are the brand new technologies that seem promising for durability/traction/cost/etc. ? anyone have good/bad experiences with X type or Y brand?
Thanks in advance for your thoughts.

Grass,dirt,the occasional sticker(hate those things!)
Ideally I would like hardwood flooring wih some 20'x20'x1 1/4" wrestling mats.
I would appreciate advice on this too. I am looking at spending about $6-800 on this size mat.I've loked on ebay for a while,but the shipping kills me!

The ONLY surface worth training on is tatami.

tatami? you may as well roll on a cheese grater! lol

Nah, the cheese grater is used for suwari waza

Seriously, as a training surface, nothing beats tatami. It's hard wearing, and just plain hard (in winter it feels like concrete). Apparently some of the newer materials that try to emulate tatami aren't too bad, from what I've heard, but compared to tatami....well, there's just no comparison.

I must be thinking of the wider pitch tatami used in certain rooms of houses in Japan.
I wouldn't think profuse sweating would be too good for it. how about the smell of sweat built up in the weave for years? I associate tatami in Japan with formal and dining areas...not with gyms. although Akido might use tatami now that I think of it, but those guys don't need to sweat right?

In any event, it's an idea to consider but I'm pretty sure I can't afford the good stuff, real or synthetic tatami.

I chose to use puzzle mats from Zebra. They are working out well so far. Firm enough for kicking, soft enough for grappling. No hard throws though.

That picture looks like its someones personal home basement and even if it isn't I wish my basement had that!!

I remember pics of your basement dojo...very cool. please excuse the barrage of questions: how thick are the puzzle mats? are they hard to clean or slipery?
am I seeing that right? each mat square is about 32 inches?

In Scotland, I have the privellage of training on real tatami, imported from Japan. It's a little harder than an artificial mat, more like hitting the ground without padding.