The good news: the technology for pellets has greatly improved and most of the side effects listed in #1 have been greatly reduced with the new Testopel pellets. For example, one recent study showed extrusion and infection rates of only %, an admirable improvement to say the least.  Although the study was sponsored by the manufacturer, I think everyone agrees that these pellets are a significant advance over the prior, being smaller and with more tight quality control for contaminants leading to infection.
After the 1 st intramuscular injection of 1000 mg testosterone undecanoate to hypogonadal men, mean Cmax values of 38 nmol/L (11 ng/mL) were obtained after 7 days. The second dose was administered 6 weeks after the 1 st injection and maximum testosterone concentrations of about 50 nmol/L (15 ng/mL) were reached. A constant dosing interval of 10 weeks was maintained during the following 3 administrations and steady-state conditions were achieved between the 3 rd and the 5 th administration. Mean Cmax and Cmin values of testosterone at steady-state were about 37 (11 ng/mL) and 16 nmol/L (5 ng/mL), respectively. The median intra- and inter-individual variability (coefficient of variation, %) of Cmin values was 22 % (range: 9-28%) and 34% (range: 25-48%), respectively.