A cheshire eyepiece is a handy tool every dob/nwetonian owner should have. Be aware, laser collimators rarely are tuned themselves, you have to first tune them off a perfectly collimated scope first (I adjusted mine off a maksutov).But if you can get one - tuned laser collimators make the job of getting a reasonable tuning for your scope very easy. However, if you want the best - you can't beat a cheshire for accuracy. www.andrewscom.com.au have the cheapest collimation tools I've seen both cheshire and laser.