Welcome to Tractorbynet, Countrybumpkin, glad to have you join us. I'm not sure whether anyone can help you a great deal with your question. It's kind of like someone asking whether to get a manual transmission or an automatic in a truck. Some folks have real strong opinions one way or the other; some are happy driving either. The important point is that it's only that person's opinion. They are all "good" transmissions, so the right one for one depends on several things: (1) what kind of work you'll be doing (mostly FEL work? plowing? mowing? long straight runs? a lot of maneuvering in tight places?), (2) what kind of experience have you had (I know you said you're new to the compact tractor world, but have you been operating big agricultural equipment, or new to tractors in general), (3) how fast do you want to get jobs done?, (4) is the price difference important to you?, (5) will you use it enough for a little difference in fuel economy to be important, etc.
OK . . ., now I'll give you my opinion. /forums/images/graemlins/wink.gif I prefer the HST even though I've got more experience with manual transmissions. The HST requires less effort; don't have to use the clutch or move a lever to change directions, I can more easily precisely control speed, especially very slow speeds when necessary; no worry about slipping a clutch. Safer in my opinion, especially for new operators, don't have to worry about having it in the "right" gear, stops quickly just by taking your foot off the pedal, rarely have to use the brake, don't have to worry about a wet shoe slipping off the clutch pedal, etc. Now some folks want a manual transmission. The HST uses some horsepower so you have just a little less to the wheels; not important to me since the HST would spin the wheels so I didn't need any more power to the wheels. The manual transmission might get just a little better fuel economy; again not important to me because the difference was too small to matter for the amount I used my tractor. If you're making long runs, as in plowing, planting, or spraying chemicals, the manual transmission may provide a more consistent ground speed. I guess you could say the GST is in between. I've never even used one myself, but you have the more direct, postive drive to the wheels, yet can shift without clutching. The only complaint I recall reading is that there is a slight lag time when shifting, and if you're going downhill at the time, it might feel like it's going to run away. I think those who understand that transmission know how to handle that, so for some people and some uses, it's the right choice.
Hope this helps just a little bit; the choice is yours.