I use opi axxium coloured soak off gel and i love it. It lasts forever on my clients without chipping. My mum had it on and couldn't get back to me for it removing for 6 weeks and although there was a huge growth line, there was not a single chip, i was amazed!! x
i have clients who have it on from just under 2 weeks and some others who get up to five and a half weeks so it depends on the nails but i love it. its a thicker product than shellac so it has more of an overlay feel in comparison. its better for imperfect nails. i think shellac is great on good nails but mine peel and it seemed to lift the shellac and similar paint on gels. the axxium is in pots and is thicker more like other brands such as biosculpture. even though opi now do a paint on gel called gelcolor im not tempted away from my axxium.