T5 bulbs have worked well for me. I'd get the most intense illumination you can afford and keep the plants as close to the bulbs as you can without physical contact, which will burn leaves. I'd also put a reflector, like aluminum foil, around the sides. With intense light, you have compact growth and deep green leaves. You have the best chance for a successful transition to real sunlight.
p.s. Cuttings started before late January may outgrow the lights by April / May.