I went through this same choice.
I ended up going with a Zel "Spartan"
Number 1 reason: Milled receiver.
That's a personal preference though and in no way implies anything about the Safety Harbor (Second choice). I just like the idea of a huge hunk of metal as the receiver.
I went with a 24" to keep it in the "in between" heavy-30's and short-18's. Seems about perfect.
I've fired it offhand (doesn't have heavy rails) and actually not bad. It is BIG, but manageable.
Some issues with extraction, but from my Mosin Nagant days, I don't really mind at all. Anyone that shoots a lot of surplus in M91/30's or M44's knows the sticky case issue.
It's no Barrett or Windrunner, but it fit the budget, and I was able to throw together a lower with an old A2 stock (Limbsaver 1" is a necessity) and old lower.
I went with the standard brake, and did not want a heavy "tank style". The regular brake does it's job.
I hadn't worked with Safety Harbor but Zel was very nice with their emails. The instructions were clear cut and overall, I like the design.
It really comes down to personal preference. I ended up with the Spartan, and love the heavy duty milled upper. So far has handled American Eagle and Surplus 50bmg without an issue, out of the box (Make sure you clean it and break in the barrel correctly)
These things are so much fucking fun