My two cents worth....'coz I was in your shoes not along ago and I spent over a year researching & looking around before I handed over my hard-earned.
Years ago I used to rip around on a rigid with 26" wheels. There was rarely a day I didn't ride it in my teens & early 20's. I still remember how that bike felt.
Then, about 2 years ago (now in my late '30's) I decided to get back into mtn bikes.....fuck me, things have changed.
First question you need to answer: What are the trails you intend to ride like? Steep or flat? Rocky & rough or smooth & groomed? All of the above?
(if the trails are a bit of everything, you need a bike that can handle the worst of it, not a bike that only handles the nice stuff...)
I was initially convinced that a HT was all I needed (same old reasons - budget, won't ride much, don't need full sus, I'll go full sus down the track if I want to..... etc etc....)
....but a mate with a lot of experience told me if I bought a HT I would be back at the LBS 12 months later upgrading to full sus. I reckon he was right.
So, here's a few key things I have learned so far:
- I tried very hard to buy second hand. You should too. Why? Full sus bikes lose a shed load of value after about 6 minutes of ownership. Gumtree, ebay, bike exchange have all got used bargains. Unfortunately, being a tall bastard I never found an XL framed bike that was the right type / price etc....but if you're in the medium / large range and you look around for a few months you will find something that has had millions spent on it going for far less than what it costs to buy or build equivalent.
- If you buy new, DO NOT let the guys at the LBS up-sell a bike way above your budget. Everywhere I went (dozen's of stores in 2 states) they tried to get me away from the entry level dualies and onto the pricier stuff. The reality is if you're not ripping trails like the fully sponsored 22 year old bloke on the cover of the magazine, a lower spec dualie is still shit loads of fun...and still faster than any HT on a rough trail with a rookie at the bars.
- Most rear shocks can be locked out anyway, so if you ride some flat, wide (boring) stuff then you kinda get a HT for free anyway....
- I spent the first 18 months riding flat pedals. They rock. You have to focus hard on the trail & anticipate stuff....so there's you skills training off-set.
- Stay up late at least 2-3 nights a week reading anything & everything on Rotorburn. There is some very experienced biker's on here....and sometimes they even share their wisdom.