In case you'd like a first-hand account, I got a trust for the lawyer mentioned in Utah.
I have a legal plan through work so it was reimbursed for me, but even if it wasn't I found the cost worth it. He walked me through it, step-by-step, and I learned a lot. I thought that alone was worth it. Beyond that, I take comfort in knowing that if I do ever need to "prove" the trust is valid, I have a lawyer who has a monetary interest in helping me.
I would guess that most roll-your-own trusts are fine (Silencer Shop Included). They'll probably only be checked if you get in trouble or die. If a couple hundred bucks isn't all that important to you, I'd go with the lawyer. If that money needs (or wants) to go elsewhere you'll probably be fine. I doubt the provision in question is going to be the make-or-break line in the trust anyway.