Looks like its Calmini for me now! Now that everyone has beaten the crap out of the BDS!
It's not that it's a bad lift, it's just it's components (springs and shocks) are just the basic components of a slight lift. For comparison, take a look at a late model full size gm lift of under 3". Straight axles both front and rear, with shocks. You basic lift consists of new lift springs for the front (basically springs which have an arc to them). For the rear, simple blocks/spacers to fit under the stock springs. Then the shocks. There really isn't real design work involved in this type of lift for this vehicle. The components don't exceed the restrictions of the suspension.
Having an IFS up front and an straight rear axle using links, it requires more design work. With a slight lift, the operation of geometry (is this such a thing, but hopefully you get the idea), hasn't really changed, just like the GM lift. Think of it like loading and unloading the vehicle. It has a compression and extension range. The lift doesn't really fall out of this range, but reaches to the limits of it.
I'm not stating for a fact that BDS, or any other lift producing company, provides a lift in such capacity, but design of a lift has several functions in mind (both manufacturer and user may want the same thing, but may not have the same results). 1 - lift of course, to provide lift of the vehicle (springs), 1a - to be able to control the added unsprung weight of larger tire/wheels (shocks/struts), 1b - capability of carrying higher weight capacities (most lift springs have a higher capacity), 2 - provide better handling in off/on-road driving situation, 2a - longer travel of the suspension components, 2b - restrict the sway during highway driving. The biggest limitation of a lift system, is the basic design of the suspension for the vehicle.
Personally, in Calmini's case, it's clear that they have done more research, design, and development in their lift 'system', thus the cost variance. Their lift does provide much of the functions of a lift system as stated above, and it's all based on the design limitations of the suspension of the vehicle. They certainly pushed the limits on certain design aspects of the suspension.
Personally, in BDS's case, their system adds lift per say (don't know as I don't have it nor have specs to compare). In comparison, they played it safe and stuck with the stock limitations of the suspension of the vehicle.
To compare to BDS, look at OME (for other types of vehicles). Their lift systems don't provide significant lift, but slight lift and better shocks. Yet, cost wise, their in comparison to Calmini's.
Do note, that suspension lift only separates the distance of the vehicle in relation to the axles. Lift wrt the ground comes from the tires. Larger diameter tires give you the necessary ground clearance under the axles.
In comparison to a slight lift in coils, adding spacers produces the same results for the coils, adding longer chosen shocks and adding a spacer to the strut, provides the same results. Only thing to consider, is that do you want to do the research for a lift and know what you want and live with the results, or purchase a lift and live with that result. Hopefully, your research will encompass all aspects you are looking for in a lift.
