I bought a manicure package that comes with two free gelish manicure session with soak-off from Lady Finger at Tampines One and had been visiting it on and off. They use the typical good quality nail polishes like OPI, etc. and are generally clean and hygienic.
Service can vary depending on the manicurist you get. Generally, the manicurists are friendly and chat with you while they are attending to you. The quality of their work is also acceptable and generally last for quite a while. However, I had a bad experience once with one who gave me a cut while removing my cuticles and did a very sloppy job of applying my polish. My advice is to treat a manicurist like how you will treat a hairdresser (or a masseuse, or any service staff, really) - find one that is good as gold and insist on having her do your nails for every session.