I would go with the tune. Reason I say that is you have a concern (power and shifting) that bugs you all the time vs an intermittent concern (occasional loss of GPS signal). So, I would recommend addressing your more consistent issue first. From personal experience I think you will be happy with the improvement from SVC tune. Had the other then switched. Very happy after the change.
Also had the external antenna and the signal gain was tremendous. It is a very worthwhile investment. Plan on another when I put a Lowrance in again.
Also had the external antenna and the signal gain was tremendous. It is a very worthwhile investment. Plan on another when I put a Lowrance in again.