Boge is a "regular" carto...the coil runs parallel to the tube walls. In a horizontal coil carto, it is on the bottom of the tube. (I hope this makes sense, it does in my head
) The regular is shorter than the XL, and yes, the only real difference is volume of juice. However, if you are punching them to use with a tank, some tanks require the XL or XXL cartos... I believe the capacity of a regular Boge is .9ml and the XL Boge is 1.2ml. Also, the regular length might have a slightly warmer vape (especially the Low Resistance or LR cartos).
Dripping attys are great for testing flavors. I keep several around, and they are dedicated by flavor (coffee, fruits/sweets, sours/tarts, mints/menthols). Some flavors are near impossible to get out of an atty, so that's why I label them. You can change flavors without mingling by dripping plain PG in between flavors until the taste of the first flavor fades to almost nothing. You should try dripping, the flavor is really clear...it's just not the most convenient way to vape. Before you add anything to a dripping atty, wrap the connector in a tissue and bring it up to your lips. Blow through the atty...half the time, you will see clear liquid on the tissue (this is primer, and does not taste good). It's a good idea to keep your atty wet always...when you open it, clip the end of the cellophane wrapper so that you can store it in that wrapper again. When you are done dripping, drip a couple of drops of plain PG on the coil before storing it.
Start by dripping about 5 drops into the atty. That should be good for a few pulls...drip more when a) vapor reduces or b) the vapor starts to taste ever so slightly burnt. Those are signs that the coil is getting dry. Before you know it, you will sense when you need to drip more juice into the atty before you will need it.
Sorry for the wall of text
So that's a heck of a saving. If I had ordered 
