Spring assist "may" not be legal in your state so check. Do they work...you bet, some have so much assist they almost fly out of your hand. Look for good steel like AUS 6 or AUS 8, or better, Solingen stainless steel (german made Boker brand) and with the Boker get the X-15 treatment (salt spray treatment). Ceramic Teflon blades are cool and very spendy, but fragile and have no place for general cutting IMO.
I keep Kershaw spring assist rescue knives (no points) on my PFD's with the glass breaker removed.
I'm sure others will have a different opinions, but that is mine. I'm never without a knife....period.
Best of luck