Let me tell you something, if it's going to increase HP, torque, and MPG, it's a lie. These are the numbers automakers want higher, don't you think if it worked they'd put it in from the factory? Also that amount of torque and HP you won't feel.

Personally, this is just my opinion but I will never tune a stock car. Tuning will basically make something that was designed to work at X level and make it work at Y level even though nothing else has changed. Tunes screw with timing, fuel injection, etc. A lot of people run them without issue, but my stance is, if you're not putting more aggressive cams and such (basically building the engine) then tuning probably isn't a good idea. I'm a truck guy, I don't know much about the cars, but I know in a stock truck if the person runs too much tuning, they are destroying the truck.

I personally run a stage 2 tune on my Audi, but that's because it has a turbo in it. I can get a lot more power out of my car with a tune, as they are crippled from factory to meet specifications for all states here in the US.

Since your car seems to be Naturally Aspirated, you wont see much gain from the tune. If you do have the turbo option, I would go for the tune as you can get decent performance increases for a small price.

I'd tune it just because why the hell not lol, but nice car BTW

In the States you don't need to report it to Insurance because its a plug and play tune, You can never go wrong with a JB4 tune but check to see if your car is compatible. My friend recently got his and you can never tell he has it and neither will the insurance.

Is it worth it?

Depends on the car not 100% familiar with the BMW tunes the 335i have an amazing tune able platform. And if the car isn't turbo don't even waste your time with an intake or anything they dontt add power.

I can tell you now for 189 pounds, it is a bad remap.

for most German cars yes. VW & Audi's are quite restricted from the factory. A nice flash/tune can really wake them up