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Aims: The accuracy and practicability of the new SRS MapCheck high resolution mutidetector array was tested and an intercomparison with our current methods for patient QA, namely film dosimetry and EPID fluence measurements was performed. Methods: Multidetector array SRS MapCheck (SunNuclear), StereoPHAN (SunNuclear) based film dosimetry with the Film QA Pro software (Ashland) and EPID (Varian) were used. Acceptance criterion for patient QA is 3%/1 mm with 95% gamma pass rate. Evaluation of all methods was performed for 10 SRS brain met cases (0.49cc mean volume). In addition, SRS MapCheck verification method was extended to further 10 SBRT lung cases (22cc mean volume) and 5 mixed SBRT cases for larger volumes (60cc mean volume) including adrenal gland, bile duct, prostate, pelvis. Regarding EPID, a tuning of the image prediction algorithm had to be performed first. Results: For the 10 SRS brain met’s cases the SRS MapCheck showed an average gamma pass rate of 97.0% ±2.3. Two cases were outside of the clinical 95% pass rate criterion with 92.4% and 93.0%. These cases are influenced by low-resolution fluence in the QA plans due to planning system memory restrictions. The 10 lung cases yielded an average pass rate of 98.4%±0.6 and the 5 other cases an average of 97.5%±2.1. Film-based dosimetry for brain cases revealed a pass rate of 99.1%±0.8, where as EPID measurements pre-optimization only 90.1%±11.3, and post-optimization 97.5%±1.9. Conclusion: All three measurement methods performed the mixture of clinical cases accurately. In terms of workflow, EPID verification is very practical as it used the on-board detector. The SRS multidetector array and film dosimetry are well comparable in terms of required work amount, when defined procedures in film preparation and a template software evaluation are used. Based on accuracy, resolution and workload, film dosimetry remains, nevertheless, the gold standard for demanding cases in clinical use.