Early exercise is great for the majority of situations. The 100k limit for ISO options can be a potential downside. If there is a spread between the strike pric

Early exercise is great for the majority of situations. The 100k limit for ISO options can be a potential downside. If there is a spread between the strike price and the FMV, only the first 100k worth of shares will be considered ISOs and the rest will be treated as NSOs. In the case of no early exercise, you could get 100k of ISOs per year for the 4 years.