I thought I'd do another swatch comparison post after putting up swatches of all my GOSH nail varnishes. The only main contender I has was an Illamasqua varnish.
"The perfect nail lacquer is developed on the basis on the most recent cosmetic and environmental know-how within its type of products. GOSH Nail Lacquer has a consistency that is easy to apply. Well covering, strong, and with a beautiful shiny and lasting finish. Formaldehyde and Toulene-free." - GOSH
"A spectrum of bold shades with a range of finishes including matt, rubber and high-gloss. Award-winning, extremely hardwearing and chip-resistant, there's an Illamasqua Nail Varnish for every shade of humanity. Apply two coats for intensity and use with Illamasqua Nail Base Coat and Illamasqua Nail Top Coat for the perfect finish." - Illamasqua
Out of the two varnishes I did have Illamasqua definitely came the closest to being a dupe however Radium has a shimmer finish and is slightly lighter than Early Green which has a basic gloss finish.
One GOSH bottle contains 8ml of product whereas Illamasqua gets you 15ml of varnish.
Both Illamasqua and GOSH varnishes have received rewards where Illamasqua won a Temptalia Editor's choice award for best Nail Lacquer while GOSH won the Beauty Bible Award for best beauty steal. I find that one coat is more than enough with Illamasqua even though they recommend you use two coats, the GOSH ones need 2 sometimes 3 coats.
One Illamasqua bottle costs £13.50 (£9.00 per 10ml) while a bottle of GOSH nail polish costs roughly £5 (£6.25 per 10 ml).