I have the best success with root riots in a heated propagator. I got sick of always buying those root riot plugs so I just started using pro-mix HP for seeds and clones, and I think it's even better(and cheaper). Regardless of what method/medium you use, HEATMATS are amazing. I think heat mats are one of the most valuable tools for a growers who sprouts seeds or roots clones. My success rate for both went from 50-80% to almost 100% every time when I started using a heat mat. With good seeds I see a long tap root emerging from the bottome of the cube or other medium within 3 days. I usually have a healthy sprout within 5 days, and I'm ready to transplant a healthy little plant into a party cup within a week of planting the seed.
I don't soak or use paper towel method- just wasted steps and time, IMO. It also adds a great probability for human error- like damaging a delicate tap root. I don't think disturbing a plant in it's most fragile state is a good idea...but hey, if it works for your, don't fix what isn't broken.