Karen B

Here is how I would look at your dilemma. With 2 of them you need to buy batteries and a charger. With the other it is charge and go.
1. Is the added expense for a charger and batteries in your budget?
2. Is the hassle of changing batteries what you want to do on the fly?
3. Making sure you have charged batteries with you a non issue?
If you answer no to at least two of these, go with the Disruptor.
If these things do not bother you or are not a big deal, the IPV D2 would be the best choice.
(These are my opinions only. Other people may tell you different.)

I am crazy about my IPV D2. It is awesome, comfortable, compact, simple and has the option for temp control if you so desire.
You also can charge it without taking the battery out if you want.
 
 
 

Good point on the built in USB charge Bebop!

The skins are nice too...
 
 

I keep forgetting that USB charging is becoming a standard in box mods. LOL I like the silicon wraps too they are soft and my mod stays in my hand. LOL

I just can't see wasting good juice, it's not the juice's fault that I have wonky taste buds. 

I have noticed people who vape help other people who vape. When I deliver parts to my customers is when I see this the most, this one guy gave me a jar full of used KPT coils, I'm slowly rebuilding them and giving them back. Another girl who's husband is in prison and left her to support the kids, (at least she's trying) I always take her 30ml bottles of juice, and tell her she's my new juice guineapig, I think she knows better because they are always her favorite flavor. I have given a lot batteries, and tanks away, and don't regret it. My accountant says I can probably write it off since I'm giving the stuff to my customers employees. 
 
I even thought about having the company name phone number and other info printed on evod batteries and giving them away as advertising, like people do with pens and stuff.

Many of the testers at vape shops have little or no nicotine.  If you then are buying a flavor that has more nicotine you are definitely going to taste a difference. Since it is happening with so many juices you have mentioned that is my first guess as to what is going on.  
 
What nicotine level are you vaping?

Hi Karen, and welcome!
When you taste flavors in the shops, they are typically in a specific tank, like the Kanger ProTank3-mini or something similar.  The type of tank and coil you use does affect the flavor, not to mention the longer you're away from analogs, the more your taste buds will change (for the better), so things will constantly taste different from day to day for several months.
I would suggest you try using the same tank and coil resistance the shop uses as their testers.  It will make replicate the flavor profile the same.
Also, the iStick mini and iStick 20W are ones I would avoid, as they fire much hotter than they specify on the display.  Move up to an iStick 30W or 50W for better performance, or switch to a completely different battery all-together.  Read the reviews posted here, and you'll get a good idea of what works and what doesn't.