Dear Friend, You want to know experience in what context? I feel both are great though I personally prefer the Straumann bone level tapered ones given the increased flexibility to make the most of patients limited anatomy such as facial undercuts, converging root tips, concave jaw structure or narrow atrophied ridges. Regards

Dear colleagues, we are doing some research with this new kind of implant and the preliminari results are very good in terms of bone level maintenance and the reduction on the need of regeneration. My personal experience in relation to the surgical aspects is that Straumann BLT implants have a greater primary stability than parallel BL and the drills fit better during the drill protocol due to the narrower tip. Very important to properly use the cortical bur to avoid pressure between the implant shoulder and the cortical bone. Best regards

Dear colleagues, 

i agree with the answer of Alberto Ortiz-Vigon. Within the limitations of our dental office, we have gathered the same clinical experience concerning the difference between parallel and tapered implants (especially Nobel Biocare products). We consider parallel implants to be more applicable in thin and very cortical ridge proportions, whereas the tapered ones may be used in more cancellous bone in order to guarantee primary stability. Therefore, the length reduced coritcal burs should especially given consideration when dealing with those tapered implants. 

Best Regards