I have 3 or 4 of the M25, 1 M50, 1 M60U and 2 M150. If you are deciding between the M25 and M50, I think the M25 is easy to hang and worth the cost savings. If you are going to spend what the M50 cost, I'd jump up to the M60U for a run and gun stand or the m150 for a more established setup. I've found the M60U for only about $20 more than the M50 and it's much lighter.
Bottom line:
Cheapest option and don't need mobility: M25
Need the most mobility and lightest option: M60U
Going to not move stand often, want the most comfort and don't mind spending a bit more: M150