The stihl oem puller is good because can pull out the seal without damage it , ( in most of cases ) but its expensive i agree with that
The husqvarna oem pullers are good,inexpensive, but you must buy 3 of them for the most models
The ebay pullers do good job , depent of seals bigs smalls positions e.t.c
Drilling the seal with a 1 mm drill not a problem to bearings because of fine shavings
Screwdrivers with notces do very good job in most of cases and cost nothing