I have used two kinds. I have a .223 cartridge-shaped laser and I've borrowed a universal laser that expands once you slide it down the muzzle. I can't remember either brand name but they were cheap. Both got me on paper and grouping less than an inch off bullseye at 50yd.

They'll get you on paper

worth it now that ammo is $2 a shot

Wow this is highly coincidental, cause just today I pulled out my universal one and the batteries were all corroded. I was thinking it would be cheaper to by a whole new one, than just get batteries.
The universal ones aren't really "bore" sights, as they go in the barrel and not the chamber/bore, but that is just me being picky ;-) My universal worked well, and like others have said, gets you on the paper first shot but still needs to be fine-tuned. If you get the universal, make sure it is sitting in the barrel nicely, as mine would kinda slide forward a bit and not do the job.

Make sure you still field site it

I have never used a high end one and can not rule out the possibility that you get what you pay for. However I do own a 308 she'll style bore sight. It is great and does the hard part for you. You'll still have to dial it in but it gives you a head start, no more guessing where it hit the dirt.

If you can remove the end and look down the sight, it seems you could mount the gun, aim it at the bullseye looking down the barrel, lock the clamp, then match your sight to the bullseye.