The 1500€ sound quiet alot, but you should consider:

1. No wasted weekends for MR (and nights looking out for fares) especially a MR for even 70K is far more expensive

2. How often would you use your SEN/*G status and profit from it ./. FTL

3. Do you have a specific route (longhaul, own LH lounge, likely to OP-UP SEN´s) ?

4. Do you want to profit from things like Companion award within the next year and the extension prevents you from loosing this perk?

And after all: How important is the shiny piece of plastic for your ego