What Stu Said (about tacking with a wheel). I've done it with both a tiller and a wheel thousands of times, and I prefer the wheel. As for "mainsheet access" - as I said, it's RIGHT THERE if you stand in front of the wheel.
As for "pro sailors.... choose tillers 100% of the time" - I had no idea I could make money single-handed sailing. Oh wait: a guy gave me $100 for moving his boat up the coast, which I did single-handed. So I'm a "pro sailor"! And I prefer a wheel, so your statement is false.
A few other points: In the Single-handed races I've been in (many), I'd say over 90% of the entrants were wheel-steered (the exceptions being very small boats or moderate-sized out-and-out racers). And many of these entrants had their choice of boats to use, presumably some with tillers.
Which brings me to my next point: it's almost impossible to BUY a tiller boat unless it's a day-sailer or racing boat. So where are all these "pro sailors" getting all these tiller boats?
Back to the actual topic: Single-handing a Catalina 25. I do notice in the pic the wheel is FAR back in the cockpit, so even in front of it you'd have to reach (a bit) to get to the mainsheet/traveller, and any lines you have on the cabin-top. For all I've said about preferring a wheel, I think ON A BOAT THAT SMALL, a tiller is probably a better choice. Not specifically for single-handing, but just for general cockpit-logic reasons.
druid