Curry, I've only used the Premium 1 from SRD, but I think its a good choice for a number of reasons. The two approaches that have a strong case are: 1) buy cheap, you'll brutalize it and 2) spend a little more for one that has reasonable prices on replacement components. I think both approaches are quite reasonable.
Latigo has a heavy draw. Some don't like this, but opt for another material for reasons I'm not sure are sound. Ease of stroke isn't the objective, a well maintained edge is. A number of experienced users and at least one honemeister, first use a heavy draw strop (such as that latigo or the Illinois series), then a light draw strop such as most of the premium SRDs. I started using an Illinois before the SRD premium 1, and the edges have been noticeably better. So even if you have a latigo and get another one at a future date, the high draw of a latigo could have a strong place in your toolset - using before the lower draw strop of your choice.
The 3" width. I avoided them, 'cause each one I tried gave issues w/ cupping (longitudinal warp), where leather doesn't stay flat across the width - either edges are raised or the center is raised. I can't speak for the SRD latigo, but the Premium 1 has stayed totally flat, and impressed me alot. If anyone can make a 3" width in Latigo and have it stay flat, I'd bet on the SRD. Plus, if it doesn't, as you say - replacements are reasonable and don't have to be latigo.
It sounds like you can't go wrong w/ either approach. A beater blade with the edge dulled, would be a great practice tool for learning the stropping. It won't give you the fine detail of the stiction or suction a fine edge develops while stropping, but that will come later. Initially, keeping only enough pressure to have all of the edge remain in contact, and mastering the all-important flip at the end of a stroke is the first objective. The finest thread I've seen on learning was from Glen's 3/11 beginner's tips thread.
http://straightrazorpalace.com/begin...ch-2011-a.html
Best of luck w/ your plunge into the best shaves there are.